JP4888723B2 - Band saw type cutting device for condenser - Google Patents

Description

  The present invention relates to a condenser band saw type cutting device and a cutting method thereof, and particularly disposed in a condenser main body at the time of dismantling of a condenser for a turbine generator installed in a thermal power plant or a nuclear power plant. The present invention relates to a band saw type cutting device for a condenser for cutting and removing a large number of thin tubes for heat exchange from a condenser main body and a cutting method thereof.

  Turbine generator condensers installed in thermal power and nuclear power plants have water chambers connected to both sides of the condenser body, and the cooling water (seawater) supplied to these water chambers is used as the condenser body. The high-temperature steam discharged from the turbine is cooled by supplying it to several thousand (for example, 14,000) heat exchange tubes (hereinafter simply referred to as “tubes”) disposed therein.

  Conventionally, the work of disassembling and cutting such a condenser is performed by first separating the water chamber from the condenser body and then manually operating the condenser body by using a gas fusing device. Was demolished. This is because the periphery of the condenser is a confined place due to a large number of existing objects such as pipes and scaffolds, and for this reason, manual work using a gas-type fusing device has been mainstream. Thousands of tubes are installed inside the condenser body, and these tubes were also cut with a gas-type fusing device. However, when reusing the cut tubes, gas must be used. In the case of the conventional fusing method, the state of the melted cross section (cut surface) of the tube was bad, and post-processing was necessary.

  On the other hand, if the tube is cut using the band saw type cutting device disclosed in Patent Document 1, the state of the cut surface of the tube becomes good. In this band saw type cutting device, a pair of sheaves are horizontally arranged (placed so that the rotation axis of the sheave is directed in the vertical direction), and an endless band saw blade is spanned between the pair of sheaves. Is a device that cuts the object to be cut by lowering the cutting means by an up-and-down moving mechanism and pressing a band saw blade against the object to be cut disposed below the cutting means.

However, a general band saw-type cutting device as disclosed in Patent Document 1 has a large number of pieces to support the cutting means including a pair of sheaves, a band saw blade, and a sheave rotation drive mechanism, and the lifting mechanism. A large frame made by assembling this steel material is required, and its outer shape is large. Therefore, the conventional band saw type cutting device has a problem that it cannot be installed in a narrow space around the condenser.
Japanese Patent No. 2967800

  The present invention has been made in view of such circumstances, and is a condensate that can be installed in a narrow space around a condenser and can cut a tube disposed in the condenser body. It is an object of the present invention to provide a dexterous band saw type cutting device and a cutting method thereof.

Condensate dexterous band saw type cutting equipment of the present invention, in order to achieve the object, the two ends together is disposed condenser body, the tube plate attached to both end openings of the condenser body part is a cutting device having a saw blade for cutting the large number of heat exchange capillary supported at its both ends near as to place the pair of sheaves horizontally, the endless on the pair of sheaves A cutting means that stretches the band saw blade with a predetermined tension and horizontally rotates the band saw blade between the pair of sheaves, a pair of guide members that guide the pair of sheaves to move up and down, and the pair of sheaves. And a lifting / lowering means for moving up and down along the pair of guide members, wherein the pair of guide members are attached to the condenser main body via bolts provided in advance on the tube plate. It is detachably fixed, By the band saw blade to move downward along the pair of guide members by serial lifting means, it is characterized in that the heat exchange capillary is cut.

According to the present invention, the pair of guide members constituting the band saw type cutting device are detachably fixed to the condenser body. That is, the condenser main body having a large structure was used as a large frame necessary for supporting the cutting means and the lifting means of the band saw type cutting device. Thereby, since the cutting means, the guide member, and the lifting / lowering means are only arranged in the narrow space around the condenser, the cutting means, the guide member can be installed in the narrow space around the condenser. And the tube arrange | positioned in the condenser main body can be cut | disconnected by each operation | movement of a raising / lowering means.

According to the present invention, a large number of bolts for fixing the water chamber protrude outwardly on the tube plate of the condenser body, and the pair of guide members are restored using the existing bolts. Removably fixed to the water main unit. Thereby, a dedicated member for fixing the pair of guide members is not necessary, and the pair of guide members can be easily fixed to the condenser body.

  According to the band saw type cutting device for a condenser and the cutting method thereof according to the present invention, the pair of guide members constituting the band saw type cutting device are detachably fixed to the condenser main body. It can be installed in a small space, and the tube disposed in the condenser main body can be cut. Further, during the cutting, since the cutting is continued after fixing the pair of guide members to the condenser body, the cutting can be performed stably.

  DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of a condenser band saw type cutting device and a cutting method thereof according to the present invention will be described below in detail with reference to the accompanying drawings.

  FIG. 1 is a perspective view showing a state in which a condenser band saw type cutting device 10 according to an embodiment is detachably fixed to a condenser main body 12, and FIG. 2 is a band saw type cutting for a condenser shown in FIG. FIG. 3 is a front view of the apparatus 10 and FIG. 3 is an assembly perspective view of the band saw type cutting apparatus 10 for a condenser. 4 is a top view of the condenser band saw type cutting device 10 shown in FIG. 1, and FIG. 5 is a right side view of the condenser band saw type cutting device 10 shown in FIG.

  The condenser band saw-type cutting device 10 is disposed in the condenser main body 12 and supported at both ends thereof by tube plates 14 attached to both end openings (not shown) of the condenser main body 12. This is a cutting device for cutting a large number of the tubes 16, 16... (See FIG. 4) in the vicinity of both ends thereof.

  As shown in FIG. 3, the condenser band saw-type cutting device 10 includes a pair of guide blocks 18 and 20 and a beam portion 22.

  The guide block 18 arranged on the right side in FIG. 3 includes a guide rail (guide member) 24 arranged in the vertical direction, a sheave holding frame 26 provided so as to be movable up and down along the guide rail 24, and the sheave holding frame. 26, a drive sheave 28 that is rotatably attached to the horizontal direction 26, a band saw blade motor (cutting means) 30 that rotates the drive sheave 28, and a feed screw rod (elevating means) 32. The lower end of the feed screw rod 32 is rotatably supported by a bearing 36 of a leg portion 34 formed at the lower portion of the guide rail 24, and the upper portion is screwed into a nut portion 38 fixed to the sheave holding frame 26. Yes. Further, the upper end of the feed screw rod 32 is rotatably supported by a bearing portion 40 formed on the beam portion 22. Therefore, when the feed screw rod 32 is rotated forward / reversely, the sheave holding frame 26 is moved up and down along the guide rail 24 together with the drive sheave 28 and the band saw blade motor 30. A motor (lifting / lowering means) 42 that rotates the feed screw rod 32 is supported by the beam portion 22.

  The guide block 20 arranged on the left side in FIG. 3 includes a guide rail (guide member) 44 arranged in the vertical direction, a sheave holding frame 46 that is provided so as to be movable up and down along the guide rail 44, and the sheave holding frame. 46, a driven sheave 48 that is rotatably mounted in the horizontal direction, and a feed screw rod (elevating means) 52. The lower end of the feed screw rod 52 is rotatably supported by a bearing 56 of a leg portion 54 formed at the lower portion of the guide rail 44, and the upper portion is screwed into a nut portion 58 fixed to the sheave holding frame 46. Yes. Further, the upper end of the feed screw rod 52 is rotatably supported by a bearing portion 60 formed on the beam portion 22. Therefore, when the feed screw rod 52 is rotated forward / reversely, the sheave holding frame 46 is moved up and down along the guide rail 44 together with the driven sheave 48. A motor (lifting means) 62 that rotates the feed screw rod 52 is supported by the beam portion 22. The driven sheave 48 is supported by the sheave holding frame 46 so as to be slidable in the horizontal direction. Further, the driven sheave 48 is moved in the horizontal direction by the jack 64 of FIG. 2 mounted on the sheave holding frame 46, and the separation distance from the drive sheave 28 is adjusted. Accordingly, when the driven sheave 48 is slid and moved away from the drive sheave 28 by the jack 64, the endless band saw blade 66 spanned between the drive sheave 28 and the driven sheave 48 is stretched with a predetermined tension. The

  The above-described guide blocks 18 and 20 are detachably fixed to the condenser main body 12 by using bolts 68, 68... Protruding around the tube plate 14 with respect to the condenser main body 12. These bolts 68, 68... Are existing bolts for attaching a water chamber (not shown) to the condenser body 12 via the tube plate 14. Of these bolts 68, 68 ..., the bolts 68, 68 ... provided along the vertical side of the tube plate 14 are penetrated through the guide rail 24 (44) of the guide block 18 (20) as shown in FIG. The guide block 18 (20) is detachably fixed to the condenser body 12 via the tube plate 14 by passing the hole 24A (44A) and fastening the nut 70 from the front side.

  Similarly, in the beam portion 22, a pair of brackets 72, 72 provided on the beam portion 22 are tubed by bolts 68, 68... Provided along the upper side of the tube plate 14 and nuts 70, 70. It is detachably fixed to the plate 14.

  Next, the operation of the condenser band saw type cutting apparatus 10 configured as described above will be described.

  First, the guide blocks 18 and 20 and the beam portion 22 are connected to the condenser main body 12 by using the bolts 68, 68... And the nuts 70, 70 as shown in FIGS. Secure through. As a result, the condenser band saw type cutting device 10 is detachably fixed to the condenser body 12.

  In this fixed state, the portion of the endless band saw blade 66 spanned between the drive sheave 28 and the driven sheave 48 that actually contributes to cutting circulates in the direction of arrow A as shown in FIG. One side part. Moreover, the one side part which contributes to this cutting | disconnection is set to the part located inside the condenser main body 12 (within 100 mm) predetermined length with respect to the tube sheet 14, as shown in FIG. Therefore, by cutting this portion in the vertical direction, the end portions 16A, 16A,... Of the tubes 16, 16 connected to the tube plate 14 are separated from the condenser body 12 together with the tube plate 14.

  When the cutting is actually performed, the band saw blade 66 is previously positioned in parallel above the condenser main body 12, and the drive sheave 28 is driven while the motor 30 is driven to move the band saw blade 66 in this state. And the driven sheave 48 are moved downward at the same speed. As a result, the ends 16A, 16A of the tubes 16, 16... Are cut from the position of the two-dot chain line in FIG. By performing this operation to a position below the tube plate 14, the end portions 16A, 16A of the tubes 16, 16,..., Together with the tube plate 14 and the end portion 12A of the condenser main body 12, as shown on the left side of FIG. It is cut and separated from the condenser body 12.

  Next, the characteristics of the condenser band saw type cutting device 10 will be described.

  The condenser band saw type cutting apparatus 10 has a pair of guide rails 24 and 44 constituting the band saw type cutting apparatus 10 fixed to the condenser body 12 in a detachable manner. That is, as a large frame necessary for supporting the cutting means (sheaves 28, 48, motor 30, band saw blade 66) and lifting means (feed screw rods 32, 52, motors 42, 62) of the band saw type cutting device 10. A condenser main body 12 having a large structure is used instead.

  Thereby, in the narrow space around the condenser, the cutting means, the guide rails 24, 44, and the lifting means are only arranged, so it can be installed in the narrow space around the condenser, The tubes 16, 16... Disposed in the condenser main body 12 can be cut by the operations of the cutting means, the guide member, and the lifting means described above.

  Further, the pair of guide rails 24 and 44 are detachably fixed to the condenser main body 12 via bolts 66, 66... That is, the tube plate 14 of the condenser main body 12 is provided with a large number of bolts 66, 66... For fixing the water chamber, and protrudes outward, and the existing bolts 66, 66. A pair of guide rails 24 and 44 are detachably fixed to the condenser body 12. Thereby, the exclusive member for fixing a pair of guide rails 24 and 44 becomes unnecessary, and a pair of guide rails 24 and 44 can be fixed to the condenser main body 12 easily.

  Moreover, in the band saw type cutting device 10 for condensers of embodiment, since the tube sheet 14 to which a pair of guide rails 24 and 44 were fixed is separated from the condenser main body 12 by the band saw type cutting device 10, cutting is continued. Then, the band saw type cutting device 10 falls with the tube plate 14. Therefore, it is necessary to separately fix the pair of guide rails 24 and 44 to the condenser body 12 at a cutting position in the middle of cutting that does not affect the cutting operation. Examples of the fixing method include using a bracket shaped so as to straddle the tube sheet 14, welding one end of the bracket to the guide rails 24 and 44, and welding the other end of the bracket to the condenser main body 12. Also, the fixing method is not limited to welding using a bracket, and any fixing method can be applied. After fixing the pair of guide rails 24 and 44 in this manner, cutting is continued.

The perspective view which showed the state by which the band saw type cutting device for condensers of embodiment was detachably fixed to the condenser main body 12 Front view of the condenser band saw type cutting device shown in FIG. Assembly perspective view of band saw type cutting device for condenser Top view of the band saw type cutting device for condenser shown in FIG. Right side view of the condenser band saw type cutting device shown in FIG. Expanded cross-sectional view of the main part showing the mounting structure of the guide block to the tube sheet The perspective view which showed typically the cutting method by the band saw type cutting device for condensers Explanatory drawing which showed the cutting position of the tube by the band saw type cutting device for condensers

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 ... Band saw type cutting device for condensers, 12 ... Condenser main body, 14 ... Tube plate, 16 ... Tube, 18, 20 ... Guide block, 22 ... Beam part, 24 ... Guide rail, 26 ... Sheave holding frame, 28 DESCRIPTION OF SYMBOLS ... Drive sheave, 30 ... Band saw blade motor, 32 ... Feed screw rod, 34 ... Leg, 36 ... Bearing, 38 ... Nut, 40 ... Bearing, 42 ... Motor, 44 ... Guide rail, 46 ... Sheave holding frame 48 ... driven sheave, 52 ... feed screw rod, 54 ... leg, 56 ... bearing, 58 ... nut, 60 ... bearing, 62 ... motor, 64 ... jack, 66 ... band saw blade, 68 ... bolt, 70 ... Nut, 72 ... Bracket

Claims (1)

A band saw that is arranged in the condenser body and cuts a large number of heat exchange tubules in the vicinity of both ends supported by the tube plates attached to both ends of the condenser body. a cutting apparatus having a blade with placing a pair of sheaves horizontally, horizontally rotating the saw blade between a pair of sheave endless of the band saw blade in the pair of sheaves and stretched at a predetermined tension A band saw type comprising: cutting means for causing the pair of sheaves to guide the pair of sheaves so as to be movable in the vertical direction; and lifting means for vertically moving the pair of sheaves along the pair of guide members In the cutting device,
The pair of guide members are detachably fixed to the condenser main body via bolts provided in advance on the tube plate, and the band saw blade moves downward along the pair of guide members by the lifting means. The condenser saw band saw type cutting device, wherein the heat exchange thin tube is cut.

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